A new high-resolution chronology for the late Maastrichtian warming event: Establishing robust temporal links with the onset of Deccan volcanism
A new high-resolution chronology for the late Maastrichtian warming event: Establishing robust temporal links with the onset of Deccan volcanism
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DOI：
10.1130/g39771.1
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发表时间：
2018-02-01
期刊：
影响因子：
5.8
通讯作者：
Zachos, James C.
中科院分区：
文献类型：
--
作者：
Barnet, James S. K.;Littler, Kate;Zachos, James C.
马斯特里赫斯晚期变暖事件的定义是，全球气温上升类似于2.5-5摄氏度，发生在类似150-300K.Y的范围内。在白垩纪-古近纪(K-PG)大灭绝之前。这一短暂的变暖事件传统上与德干圈闭(印度中西部)火山活动的主要脉冲有关；然而，与辐射成因测年方法相关的巨大不确定性长期以来阻碍了确定的相关性。在这里，我们提供了来自南大西洋的新的高分辨率、单物种、海底稳定同位素记录，并根据更新的轨道调谐年龄模型进行了校准，以提供修订的事件年代学，然后我们将其与主要德干圈闭喷发阶段的最新放射成因日期相关联。我们的数据显示，深海变暖的开始，在不确定的情况下，与德干火山活动主期的开始重合，这强烈地表明了因果联系。深海变暖的开始与405K.Y是同步的。最小偏心率，不包括仅受轨道强迫的控制，尽管在温室气体变暖期间，碳循环对轨道进动的敏感性增强是明显的。对德干引起的气候变化有更准确的了解，将为今后的工作铺平道路，重点放在这些前兆气候变化在K-PG大灭绝中的基本作用。
The late Maastrichtian warming event was defined by a global temperature increase of similar to 2.5-5 degrees C that occurred similar to 150-300 k.y. before the Cretaceous-Paleogene (K-Pg) mass extinction. This transient warming event has traditionally been associated with a major pulse of Deccan Traps (west-central India) volcanism; however, large uncertainties associated with radiogenic dating methods have long hampered a definitive correlation. Here we present a new high-resolution, single species, benthic stable isotope record from the South Atlantic, calibrated to an updated orbitally tuned age model, to provide a revised chronology of the event, which we then correlate to the latest radiogenic dates of the main Deccan Traps eruption phases. Our data reveal that the initiation of deep-sea warming coincides, within uncertainty, with the onset of the main phase of Deccan volcanism, strongly suggesting a causal link. The onset of deep-sea warming is synchronous with a 405 k.y. eccentricity minimum, excluding a control by orbital forcing alone, although amplified carbon cycle sensitivity to orbital precession is evident during the greenhouse warming. A more precise understanding of Deccan-induced climate change paves the way for future work focusing on the fundamental role of these precursor climate shifts in the K-Pg mass extinction.